Ab initio density functional theory (DFT) has been used to investigate the thermal properties of the CuBr0.5Cl0.5 alloys over a wide range of temperature. Using the quasiharmonic approximation (QHA) for the some physical quantities of interest such as heat capacity at constant volume and entropy are calculated and discussed. The theoretical results show good agreement with the available experimental data for CuBr and CuCl. The present results show that symmetric and asymmetric structure of CuBr0.5Cl0.5 have a good agreement with the calculatingly value for heat capacity.
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